From the University of California, San Francisco, CA. Corresponding author. Mary E. Lynch, RN, MS, MPH, PNP, University of California, San Francisco, CA. E-mail: mary.lynch@nursing.ucsf.edu. 0882-5963/$ see front matter doi:10.1016/j.pedn.2008.01.001 WHY SHOULD YOU be a member of the Society of Pediatric Nurses (SPN)? To be an effective member, however, you must first consider your clinical practice focus. By becoming a pediatric nurse, you have made a serious professional practice commitment to provide health care for healthy or sick children and their families in various caregiving environments. Your clinical practice focus reflects individuals with a substantial health–illness trajectory that includes crucial health promotion interventions such as obesity prevention, pediatric critical care, and palliative/end-of-life care for dying children. Your population is dynamic not only in growth and development but also in the complexity of the unique health care needs that are experienced by infants, children, and adolescents. These young and vulnerable individuals are at risk for numerous health care challenges, which are also influenced by multiple socioeconomic factors that impact on their access to health care services and subsequent risk of experiencing health care disparities. Two examples of these complex pediatric health challenges include childhood obesity and childhood cancer. Approximately one third of all children and adolescents are overweight or obese (Ogden et al., 2006). These individuals are at greater risk for experiencing numerous health conditions including type 2 diabetes, fatty liver, orthopedic problems, sleep apnea, and depression. However, overweight and obese children and adolescents are also more likely to experience adult health conditions at an earlier age including coronary artery disease, kidney failure